工艺参数对聚脲甲醛包覆环氧树脂微胶囊物性的影响

以聚脲甲醛为囊壁、双酚A 型环氧树脂( E-51) 和正丁基缩水甘油醚(501 # ) 混合物为囊芯, 采用原位聚合法合成聚脲甲醛包覆环氧树脂体系微胶囊。通过L16 (45 ) 正交试验研究了原料配比、终点p H 值、搅拌速率、酸化时间、平均升温速率等工艺参数对微胶囊的合成状态、粒径大小和分布的影响规律, 并利用扫描电子显微镜(SEM) 、光学2摄影显微镜(OM) 进行表征。结果表明: 原料配比和终点p H 值对微胶囊的合成状态有显著影响;适当延长酸化时间和增加升温速率, 有利于增加微胶囊表面的粗糙度; 随着搅拌速率的增加, 微胶囊的粒径减小、分布变窄。优化的工艺条件为: 原料配比为0. 8∶1 , 终点p H = 2. 0～4. 0 , 酸化时间为2. 0～3. 0 h , 升温速率为0. 17～0. 25 ℃·min -1 , 搅拌速率为325～350 r·min -1 。 

Effects of processing parameters on physical properties ofpoly ( urea-formaldehyde) microcapsules of epoxy resin

A series of microcapsules were prepared by in-si tu polymerization with poly (urea-formaldehyde) as theshell material and the mixture of epoxy resin E-51 and butyl glycidyl ether (501 # ) as the core material. The effect sof the processing parameters , including the mass ratio of core material to shell material , final p H value , agitationrate , acidification time and heating rate , on the state of microencapsulation , the microcapsule size and it s dist ribution were discussed by L16 (45 ) orthogonal experiment . The physical properties of microcap sules were investigatedusing scanning elect ron microscopy (SEM) and optical-photographic microscopy (OM) . The state of microencapsulation is dramatically dependent on the mass ratio of core material to shell material and final p H value. Themicrocapsule surface morphologies are better when the acidification time and heating rate are properly increased.The microcap sule size decreases and it s dist ribution narrows with the increasing of agitation rate. The optimum conditions are as follows : the mass ratio of core material to shell material is 0. 8∶1 , final p H value is 2. 0～4. 0 , acidification time is 2. 0～3. 0 h , heating rate is 0. 17～0. 25 ℃·min-1 , and agitation rate is 325～350 r·min -1 .